source: Dev/trunk/src/client/dojox/wire/ml/Service.js

dojo.provide("dojox.wire.ml.Service");

dojo.require("dijit._Widget");
dojo.require("dojox.xml.parser");
dojo.require("dojox.wire._base");
dojo.require("dojox.wire.ml.util");

dojo.declare("dojox.wire.ml.Service", dijit._Widget, {
        // summary:
        //              A widget for a service
        // description:
        //              This widget represents a service defined by a service description
        //              specified with 'url' attribute.
        //              If 'serviceType' and 'serviceUrl' attributes are specified, 'url'
        //              attribute can be omitted.

        // url:
        //              A URL to a service description
        url: "",

        // serviceUrl:
        //              A URL to a service
        serviceUrl: "",

        // serviceType:
        //              A service type
        serviceType: "",

        // handlerClass:
        //              A service handler class name
        handlerClass: "",

        preventCache: true,

        postCreate: function(){
                // summary:
                //              Call _createHandler()
                // description:
                //              See _createHandler().
                this.handler = this._createHandler();
        },

        _handlerClasses: {
                "TEXT": "dojox.wire.ml.RestHandler",
                "XML": "dojox.wire.ml.XmlHandler",
                "JSON": "dojox.wire.ml.JsonHandler",
                "JSON-RPC": "dojo.rpc.JsonService"
        },

        _createHandler: function(){
                // summary:
                //              Create a service handler
                // description:
                //              A service handler class is determined by:
                //
                //              1. 'handlerClass' attribute
                //              2. 'serviceType' attribute
                //              3. 'serviceType' property in a service description
                // returns:
                //              A service handler
                if(this.url){
                        var self = this;
                        var d = dojo.xhrGet({
                                url: this.url,
                                handleAs: "json",
                                sync: true
                        });
                        d.addCallback(function(result){
                                self.smd = result;
                        });
                        if(this.smd && !this.serviceUrl){
                                this.serviceUrl = (this.smd.serviceUrl || this.smd.serviceURL);
                        }
                }
                var handlerClass = undefined;
                if(this.handlerClass){
                        handlerClass = dojox.wire._getClass(this.handlerClass);
                }else if(this.serviceType){
                        handlerClass = this._handlerClasses[this.serviceType];
                        if(handlerClass && dojo.isString(handlerClass)){
                                handlerClass = dojox.wire._getClass(handlerClass);
                                this._handlerClasses[this.serviceType] = handlerClass;
                        }
                }else if(this.smd && this.smd.serviceType){
                        handlerClass = this._handlerClasses[this.smd.serviceType];
                        if(handlerClass && dojo.isString(handlerClass)){
                                handlerClass = dojox.wire._getClass(handlerClass);
                                this._handlerClasses[this.smd.serviceType] = handlerClass;
                        }
                }
                if(!handlerClass){
                        return null; //null
                }
                return new handlerClass(); //Object
        },

        callMethod: function(method, parameters){
                // summary:
                //              Call a service method with parameters
                // method:
                //              A method name
                // parameters:
                //              An array parameters
                var deferred = new dojo.Deferred();
                this.handler.bind(method, parameters, deferred, this.serviceUrl);
                return deferred;
        }
});